Clay soil offers some tough and unique challenges to anyone trying to grow a lawn. Not only is clay heavy and compact, but it can become waterlogged in winter and then crack in the summer! However, it’s not impossible to establish a lush lawn and here, we tell you how.
Understanding Clay Soil
Clay soil is made up of fine particles that are packed tightly together. This unique construction allows the soil to retain nutrients well, but it also results in poor drainage and limited air circulation. Under such conditions grass roots can become stressed and moss and weeds will flourish if not managed properly. The key is to work with the soil, not against it.
Choosing the Right Grass Seed
Of course, selecting the right grass seed is of paramount importance. For clay soil, you need a mix that will tolerate wet conditions, compaction, and potentially limited sunlight. The best grass seed mixes for clay soil typically contain:
Perennial ryegrass - this hardy and fast-germinating grass is ideally suited to handle wear and tear. It establishes quickly and performs well in clay soil. It does particularly well in high-traffic areas such as family gardens.
Creeping red fescue – a fine-leaved variety, creeping red fescue creates a dense lawn. It is ideal for shaded areas and tolerates low fertility well.
At Boston Seeds, our BS Childs Play Lawn Seed is made up of over 80% of the above varieties as well as other fescue varieties, and common bent.
Preparing Clay Soil for Sowing
Once you have chosen your grass seed, preparation of the clay soil is key. Address any compaction or drainage issues that are common with clay soils by following these steps:
Clear the area thoroughly – to give your seed the best possible chance of rooting successfully, remove all existing grass, weeds, and debris.
Dig the soil - using a spade or rotavator, dig down at least 15cm (6 inches), breaking up any large clumps and removing stones as you go.
Incorporate organic matter – to loosen the clay and improve nutrient availability, work in lots of organic matter such as compost, well-rotted manure, or soil improver.
Add sharp sand or grit (optional) – heavy soil will benefit from the addition of horticultural sand or grit to improve drainage. However, avoid builder’s sand, as its salt content can be harmful to plants.
Level and firm the ground - rake the surface smooth, lightly heeling it down to firm it. Finish by lightly raking again to create a fine, even seedbed.
How to Sow Grass Seed on Clay Soil
Timing is paramount! The best time to sow grass seed here in the UK is spring (March to May) or early autumn (late August to September), when the soil is warm and moisture levels are ideal.
Sow evenly - distribute the seed evenly at a rate of 35g per square metre. Whatever the size of the lawn you are sowing, we have the perfect lawn spreader to help.
Rake seeds in lightly – mix the grass seed into the top 1cm of soil by gently raking the surface.
Firm the soil - use a roller or walk over the surface of the soil to ensure good seed-to-soil contact.
Water gently - use a fine spray to keep the area moist, but avoid flooding the soil, as clay quickly and easily becomes waterlogged.
Protect the area – consider adding a net cover to the seeded area until germination (between 7-14 days), to protect against birds.
Care of Clay Soil Lawns
Once the grass has become established, keep your lawn healthy by mowing regularly, aerating once a year to improve drainage and root health (with a garden fork or aerator), and seasonal feeding. Our Lawn Fertiliser Blog has lots of useful advice on fertilising your lawn.
Grass Seed for Clay Soil from Boston Seeds
If you have a clay soil and would like something a little different to a lawn, we also offer a Heavy Clay Soils Wildflower Seed BS5P 100%, containing 24 British native (mainly perennial) wildflower species. Alternatively, our Heavy Clay Soils Wildflower Meadow Seed BS5M 80/20 is perfect for creating a natural-looking grass and wildflower meadow on clay soils.
With over 20 years’ experience of selling grass seed and lawn seed online, we offer the best varieties of grass seeds for any type of ground and any conditions. Whether you want to sow a sports pitch or a lawn to withstand children and pets, or you are looking for grass for sandy soil or grass for a shady garden, we have the perfect seed mix for you.
For any help or advice, our experienced sales team is available on email or telephone on 01205 280069.
